Hydraulically powered ski lift



United States Patent poration of Michigan Filed Jan. 7, 1965, Ser. No.424,033 3 Claims. (Cl. 104-173) This invention relates to ahydraulically powered ski lift and more particularly to a ski liftwherein the sheave of the drive terminal is driven directly by means ofa slow speed hydraulic motor.

In recent years skiing has become a very popular sport and as a resultmany ski resorts have been established in which ski lifts are installed.Such ski lifts usually employ two tower structures or terminals, as theyare usually called. One of the terminals, referred to as the driveterminal, is located at the lower end of a slope or hill and the otherterminal, called the top terminal, is located at the top of a slope orbill. Each terminal is provided with a rotatable sheave, and around thetwo sheaves there is extended a towline having bars depending therefromfor towing skiers to the top of the hill Where the top terminal islocated. The sheave of the lower or drive terminal is the one which isusually driven, the sheave of the upper terminal being an idler.

In the conventional arrangement the sheave of the lower terminal isdriven by means of an electric motor through a gear reduction of sometype. Frequently the gear reduction comprises a large bull gear keyed tothe shaft on which the drive shaft is keyed and engaging one or moresmaller gears forming a gear train to the output shaft of the electricmotor. Such a drive arrangement for a ski lift is not only noisy butover a period of time considerable wear occurs, resulting in breakdownsand the need for servicing. When it is considered that on some daysthere may be as many as 3,000 to 5,000 skiers using a ski lift to returnthem to the top of a slope, it will be realized that a breakdown of theski lift, even for several hours, can create serious problems. One ofthese problems may be a financial one if the proprietor of the skiresort has to refund admission fees to the skiers because of theirinability to use the ski lift.

It is an object of the present invention to provide a ski lift drivemechanism that is not only economical in its construction but issubstantially trouble-free in its operation.

A further object of the invention is to provide a ski lift that is quietin its operation and which employs a minimum number of parts.

In the drawings:

FIG. 1 is a side elevational view of a drive terminal for a ski liftembodying the present invention.

FIG. 2 is a fragmentary sectional view, with parts broken away,illustrating a ski lift drive arrangement of the present invention.

FIG. 3 is a fragmentary top view of a ski lift embodying the presentinvention.

Referring to the drawings and particularly to FIGS. 1 and 3, there isillustrated a ski lift which in many respects is similar to conventionalski lifts in that it incorporates a top terminal 16 and a drive terminal12. The top terminal 10 is arranged to be mounted at the top of a hillor incline, and includes the frame 14 on which an idler sheave 16 ismounted, as at 18, for rotation in a generally horizontal plane. Thedrive terminal 12 is located at the bottom of a hill or slope, and alsoincludes a sheave 20 mounted for rotation in a horizontal plane. Anendless towline 22 is trained around sheaves 16 and 20 and has bars 24depending therefrom for enabling the skiers to be towed up the hill orincline from the drive terminal to the top terminal 16. Guide sheaves 25for the "ice towline are provided on the terminals and on intermediateupright poles (not shown) which are usually erected at spaced pointsbetween the two terminals.

Drive terminal 12 comprises a main frame consisting of uprights 26 whichare suitably braced as by structural members 28, and interconnected bytransverse members 30 and a pair of longitudinally extending tracks 32.The lower end of the upright members and the bracing 28 are adapted tobe fixedly mounted on foundation members 34.

Tracks 32 may be formed as channels and are adapted to support a trolley36 as by trolley wheels 38. Trolley 36 is in the form of a horizontallydisposed yoke having a long, horizontally extending upper arm 40 and ashorter, horizontally extendnig lower arm 42 interconnected by a gussetsection 44 at one end thereof. At one end of trolley 36 there is mountedon the upper arm 40 an idler sheave 46 around which is trained a cable48. Cable 48 is anchored on the frame of the terminal, as at 50, extendsaround a second sheave 52 and has a'counterweight 54 connected to thefree end thereof. The counterweight arrangement illustrated inconjunction with the trolley 44 takes the slack out of the towline 22,and also enables the load on the towline 22 to vary considerably withoutproducing an excessive jerking movement of the towbars 24 on the towline22.

Referring now to FIG. 2, the means for rotating the drive sheave 20 isthere illustrated. Sheave 20 is keyed to a shaft 60. The upper end ofshaft 60 is journalled in a pillow block 62 mounted on a transverselyextending angle member 64 on the upper arm 40' of trolley 36. The lowerend of shaft 60 extends through a bearing 66 mounted on a transverselyextending member 68 on the lower arm 42 of trolley 36. On the lower sideof arm 42 of trolley 36, there is mounted a motor mounting bracket 70.Bracket 70 is in the form of a cylindrical shell having a flange 72bolted to the underside of arm 42. The motor counting bracket alsoincludes a lower annular flange 74 to which a hydraulic motor 76 isbolted. as as 78. The output shaft of hydraulic motor 76, which isdesignated 80, extends vertically upwardly and is coaxial with the driveshaft 60 on which the sheave 20 is keyed. The upper end of shaft 80 andthe lower end of shaft 60 are connected together in driving relation bya coupling 82. Coupling 82 comprises an upper section 84 keyed to thelower end of shaft 60, as at 86, and a lower section 88 keyed to theupper end of shaft 80, as at 90. The two sections 84, 88 of coupling 82are bolted together as by bolts 92, so that the coupling establishes adirect driving connection between the upper end of shaft 80 and thelower end of shaft 62.

Hydraulic motor 76 is powered by a drive package 94. The drive package94 is preferably in the form of an electric motor-driven pump, notillustrated, having hydraulic lines 96, 98 connected with the inlet andexhaust ports of motor 94. Drive package 94 is fixedly mounted on theground adjacent the frame of the drive terminal and the hydraulic lines96, 98 are flexible to accommodate the forward and rearward movement ofmotor 76 with trolley 36.

With the above-described arrangement, it will be noted that the driveshaft 60 is driven directly by means of the coupling 82 by the outputshaft 80 of hydraulic motor 76. This arrangement not only provides thetowline 22 with a smooth operation, but it also eliminates the numerousparts, including gears, that are used in a conventional arrangementwherein the drive sheave 20 is driven by an electric motor through agear train. Even more important is the fact that the direct hydraulicdrive of the drive shaft 60 has a minimum of moving parts which areessentially trouble-free in their operation. This means that the likelihood of a breakdown in the operation of the ski lift is unlikely, andconsequently interruption of the service provided by the ski lift iseliminated.

I claim:

1. A drive terminal for a ski lift comprising a frame adapted to besupported on a ground surface, a horizontally extending guide track onsaid frame, a trolley guided for movement on said track, said trolleyincluding a pair of vertically-spaced horizontally-extending arms, apair of vertically aligned bearings mounted one on the upper arm and oneon the lower arm of the trolley, a vertically extending shaft journalledin said bearings, a sheave keyed to the portion of the shaft extendingvertically between said bearings, a motor mounting bracket mounted onone of said arms, a hydraulic motor fixedly mounted on said bracket andhaving a vertically disposed output shaft aligned axially with saidfirst-mentioned shaft, means coupling the output shaft of the motor withthe first-mentioned shaft for rotating the sheave when the motor isenergized, a motor pump unit independent of said trolley and flexiblefluid conduits extending from said motorpump unit to said hydraulicmotor for supplying fluid under pressure to said motor.

2. The combination called for in claim 1 wherein the motor montingbracket is supported on the lower arm of the trolley, the motor beingmounted on the bracket in a position vertically below the bearing on thelower arm of the trolley.

3. The combination called for in claim 2 wherein the motor mountingbracket comprises a generally cylindrical shell disposed With its axisextending vertically, said shell having circumferentially extendingflanges at its upper and lower ends, means connecting the upper flangeof the shell with the lower arm of the trolley and means securing saidhydraulic motor to the lower flange on the shell with the output shaftextending vertically upward through the shell.

References Cited UNITED STATES PATENTS 1,556,819 10/1925 Hires 1041732,285,636 6/1942 Wallace 104-173 2,981,205 4/1961 Bannerman et al.104173 3,182,455 5/1965 Racicot 60-53 ARTHUR L. LA POINT, PrimaryExaminer.

D. F. WORTH, Assistant Examiner.

1. A DRIVE TERMINAL FOR A SKI LIFT COMPRISING A FRAME ADAPTED TO BESUPPORTED ON A GROUND SURFACE, A HORIZONTALLY EXTENDING GUIDE TRACK ONSAID FRAME, A TROLLEY GUIDED FOR MOVEMENT ON SAID TRACK, SAID TROLLEYINCLUDING A PAIR OF VERTICALLY-SPACED HORIZONTALLY-EXTENDING ARMS, APAIR OF VERTICALLY ALIGNED BEARINGS MOUNTED ONE ON THE UPPER ARM AND ONEON THE LOWER ARM OF THE TROLLEY, A VERTICALLY EXTENDING SHAFT JOURNALLEDIN SAID BEARINGS, A SHEAVE KEYED TO THE PORTION OF THE SHAFT EXTENDINGVERTICALLY BETWEEN SAID BEARINGS, A MOTOR MOUNTING BRACKET MOUNTED ONONE OF SAID ARMS A HYDRAULIC MOTOR FIXEDLY MOUNTED ON SAID BRACKET ANDHAVING A VERTICALLY DISPOSED OUTPUT SHAFT ALIGNED AXIALLY WITH SAIDFIRST-MENTIONED SHAFT, MEANS COUPLING THE OUTPUT SHAFT OF THE MOTOR WITHTHE FIRST-MEMTIONED SHAFT FOR ROTATING THE SHEAVE WHEN THE MOTOR ISENERGIZED, A MOTOR PUMP UNIT INDEPENDENT OF SAID TROLLEY AND FLEXIBLEFLUID CONDUITS EXTENDING FROM SAID MOTORPUMP UNIT TO SAID HYDRALUICMOTOR FOR SUPPLYING FLUID UNDER PRESSURE TO SAID MOTOR.